Clutch pressure plate



Feb. 20, 1940. G. T. JARRETT CLUTCH PRESSURE PLATE Filed Aug. 16, 1938 INVENTOR, 61901 6 Z J/h/i BY Gm 5? 9% ATT RNEg v the driven element, 1. e., the clutch plate.

and Fig.

Patented Feb. 20, 1940 mm mm.

CLUTCH PRESSURE PLATE George T. Jarrett, East Cleveland, Ohio, assignor to Ira Saks Application August 16,

2 Claims.

The present invention relates to an improvement in the driving member of a friction clutch assembly, More particularly, it has to do with the driving member more commonly known as the pressure plate. A clutch pressure plate'is the element, which, by means of engagement by pressure springs and operating levers, is moved inan axial direction toward and away from the other driving member, namely, the fly wheel, in order to effect engagement and disengagement with Such frictional engagement of the pressure plate with the clutch plate of course produces a substantial amount of heat. of friction, which on transmission through the pressure plate has. a deleterious effect upon the actuating elements such as the pressure springs and the operating levers.

It is therefore the general object and nature of my invention to provide an isolated and insulated portion for a clutch pressure plate, such portion being located on the side opposite to the friction engaging surface of the pressure plate and adapted to be contacted by the pressure springs and/or operating levers, My inventionis particularly beneficial where operating levers of relatively thin cross-section, such as levers formed of stamped metal, are used; or where the pressure springs and operating levers are combined into the form of a single element as in the Belleville spring type of pressure plate actuating element.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

1 and illustrating a pressure plate embodying the principle of my invention; Fig. 2 is a plan view of the right hand or rear face of the pressure plate; 3 is an enlarged sectional view of the pressure plate. 3

Now referring more particularly to the drawing, there is shown therein a driving member consisting of the fly wheel 1, whichcarries the clutch housing or cover plate 2. The other driv- 1938, Serial No. 225,134

with slots therein. The friction clutch plate i is positioned between the fly wheel i and the pressure plate 3.

The movement of the pressure plate 3 into and out of engagement with the clutch plate l is controlled by means of the Belleville spring 5 which functions both as a lever and spring element. The Belleville spring 5 is fulcrumed upon the pivot rings. 1 and 8fwhich are held in position with respect to the cover plate 2 by means of the in retaining bolts 6.

The portion 9 of the pressure plate 3 is fastened thereto by means of the rivets iii and spaced and insulated therefrom by means of the layer of insulating material ii. A shoulder i2 is 153 provided on the pressure plate 3 and serves as means for further aiding in the positioning of the separated portion 9 on the pressure plate 3. The portion 9 has a lip 13 which is adapted to be contacted by the outer edge of the Belleville spring 5, and this edge is in turn held against the lip it by. means of the retaining spring clips Hi. It will thus be seen that the operating element contacting portion 8 of the pressure plate 3 is separated and insulated from the body of the pressure plate, so that the heat of friction generated by the frictional contact of the engaging surface of the pressure plate 3 is not transmitted to the operating element 5, thus preventing the drawing of the temper and weakening of the latter.

The portion 9 also has driving lugs 53 adapted to engage with the slots in the cover plate 2. The lugs 9 are of course in radial alignment with the driving lugs 3' and form a continuation thereof.

It should be apparent torthose skilled in the art, from the foregoing description, that the principle of my invention is equally well applicable to other forms of clutch assemblies wherein the actuating elements such as operating levers and pressure springs are not combined in a single element such as the Belleville spring 5, but are in the form of individual elements.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the structure herein disclosed, provided the means stated by any of the following claims orthe equivalent of such stated means be employed.

I therefore particularly point out and diaportions being so shaped. and assembled as to form a normally complete pressure plate and including driving lug projections on the outer periphery of said portions, said projections being in registry with each other, a layer of insulating material separating said portions, and fastening means passing through both of said portions.

2. A mutli-part clutch pressure plate consisting of a friction surface-engaging portion and an operating lever contact portion, both of said 10 portions being so shaped and assembled as to form a normally complete pressure plate and ineluding driving lug projections being in registry with each other, said contact portion extending from the outer periphery of said engaging portion, centrally inwardly to a. point short of the inner marginal edge of the latter, an annular shoulder on. said engaging portion adjacentsuch inner edge of said contact portion, a layer of insulating material separating said portions, and fastening means passing through both of said portions.

GEORGE 'I'. JARRE'I'I'. 

